Re: [PATCH v3 2/8] tests/tcg/multiarch/linux-test: use portable alternative for dirent64

[Peter Maydell <peter.maydell@linaro.org>]

On Tue, 24 Mar 2026 at 13:15, Michael Tokarev <mjt@tls.msk.ru> wrote:
>
> On 20.03.2026 18:51, Alex Bennée wrote:
> > From: Matheus Tavares Bernardino <matheus.bernardino@oss.qualcomm.com>
> >
> > dirent64 and readdir64 are glibc-specific and not portable to other
> > C libraries such as musl. Define _FILE_OFFSET_BITS=64 instead, which
> > portably instructs all libc implementations to use 64-bit file offsets,
> > making readdir() and struct dirent equivalent to their 64-bit variants.
>
>
> > --- a/tests/tcg/multiarch/linux/linux-test.c
> > +++ b/tests/tcg/multiarch/linux/linux-test.c
> > @@ -16,6 +16,7 @@
> >    *  You should have received a copy of the GNU General Public License
> >    *  along with this program; if not, see <http://www.gnu.org/licenses/>.
> >    */
> > +#define _FILE_OFFSET_BITS 64
>
> Afiacs, qemu has always been built with file_offset_bits=64, one way
> or another:
>
> meson.build:
>    '-D_GNU_SOURCE', '-D_FILE_OFFSET_BITS=64', '-D_LARGEFILE_SOURCE',

Those control the compiler flags for QEMU itself. This is
a standalone test program built for the guest, and it isn't
built directly by meson.

> Now, with only 64bit host support, defining _FILE_OFFSET_BITS to 64
> makes no difference, since it is already 64 by default.

We still support 32-bit guests, though, and this is being built
for the guest architecture.

thanks
-- PMM